Cardio exercise is probably the most famous kind of exercise out there. It's used for a range of different goals, and it's useful to all of them. One misconception that often comes alongside it is that it will make you skinny, which is just not the case.


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The Myth

Now, we can take two very different routes to the myth here, and they both need a lot of detail. Usually, the beliefs are:

  • Cardio makes you skinny when you’re trying to bulk
  • Cardio alone will make you lose weight

To a very small extent, they’re true. Kind of. It is a lot more complicated than just those blanket statements, and they are both very bad ways to look at things in their own way.

Bulking Up

man training on a treadmill

Looking specifically at those people who are trying to build muscle and bulk up. The common idea here is that doing cardio exercise is going to make you lose weight. That’s what cardio is for right? Well… not really no. Cardio exercise is perfect for burning calories depending on what you do, how often, and for how long. Doing it maybe once a week though is not going to do much to your progress what so ever.

In fact, cardio exercise when you’re training is actually a really positive thing for you to do. It keeps your heart and your circulatory system in the best shape possible, which is ALWAYS a pillar of being healthy. It improves your stamina too, which is good for performance in general life, it cuts fat to make your muscle more defined… It's just a great tool to have. Don't be scared of it; you're still in control of what you do.

Losing Weight

woman training on an assault bike

The second way to look at how cardio makes you lose weight, in the long run, is by looking at the attitude of those who are trying to lose weight. A lot of people tend to follow the principle that cardio is all you need to lose weight. More specifically, people can eat what they want as long as they exercise.

Again, this is absolutely not the case, and it just will not work in the long run. Cardio is an incredibly effective way to help you burn calories, don't get us wrong. Your weight massively depends on a combination of things, though. That's all in the fundamentals of weight loss. Overall, to lose weight, you need to be making a calorie deficit in your day. That's the bottom line. You can do as much cardio as you want, but unless you're creating a consistent deficit, you're not going to lose weight if you're eating over you limit even after exercise.

The Bottom Line

Ultimately, you can do as much cardio as you want to, your weight depends almost entirely on how many calories you are consuming in a day, and what your metabolism is like. If you're eating over your caloric needs in a day, then you're going to put on weight. If you're weight training while you're going over this limit, that will be muscle. When you eat more than 250 calories over your needs, it will probably be fat too.

If you're consuming under your caloric needs after doing cardio, then you're going to lose weight. That's how losing weight works really. Cardio will just make it easier to make this calorie deficit. On top of that, cardio will help you keep the weight off as well as losing it since it increases your resting energy expenditure.

Cardio is not a bad thing. It’s vital to good health, and it comes in so many different formats that there’s always one that’s right for you. HIIT training is a great way to burn off a high number of calories while building some muscle at the same time in most cases, and LISS like walking is a great way to burn the most fat per calorie burned, which is awesome for building muscle and losing fat at the same time. Just do your homework and find what suits your needs. Cardio is not the enemy.


cardio machines

Before beginning any exercise or nutrition program, consult your physician, doctor or other professional. This is especially important for individuals over the age of 35 or persons with pre-existing health problems. Exercise.co.uk assumes no responsibility for personal injury or property damage sustained using our advice.

If you experience dizziness, nausea, chest pain, or any other abnormal symptoms, stop the workout at once and consult a physician or doctor immediately.